Clamp

ABSTRACT

A clamp having a pair of clamp arms pivotally connected intermediate the ends thereof. A novel construction allows the pivotal point to be changed, thereby producing a versatile clamp which can have slow action and a high leverage factor, a fast action and a slow leverage factor or adjustments inbetween. The length of the clamp arms are additionally adjustable. A jack screw device extends through a hole in an arcuate shaped member in one of the clamp arm ends and threadedly engages a pivotally mounted bracket on the other clamp arm in a construction which allows the movement of the pivotal point on the clamp.

llnited States Patent [191 Emerson 21 App]. No.: 464,567

[52] US. Cl 24/248 A; 24/248 SA; 24/248 R; 269/238; 269/209 [51] Int.Cl. A44B 21/00; B25B 1/04 [58] Field of Search 24/248 A, 248 L, 248 SA,24/248 BC, 248 R; 269/88, 208, 238, 209

FOREIGN PATENTS OR APPLICATIONS 582,077 11/1946 United Kingdom 269/238Primary ExaminerBernard A. Gelak Attorney, Agent, 0r.Firm--I-I enderson& Strom 57 ABSTRACT A clamp having a pair of clamp arms pivotallyconnected intermediate the ends thereof. A novel construction allows thepivotal point to be changed, thereby producing a versatile clamp whichcan have slow action and a high leverage factor, a fast action and aslow leverage factor or adjustments inbetween. The length of the clamparms are additionally adjustable. A jack screw device extends through ahole in an arcuate shaped member in one of the clamp arm ends andthreadedly engages a pivotally mounted bracket on the other clamp arm ina construction which allows the movement of the pivotal point on theclamp.

9 Claims, 5 Drawing Figures CLAMP BACKGROUND OF THE INVENTION Thepresent invention relates generally to clamps and more particularly toclamps which have an adjustable leverage factor.

Clamps are one of the earliest tools known to mankind. This may be onereason why there are 'so many different kinds of clamps in commercialand private use today. While the purpose of a clamp is to hold an objector to hold one object against another, as the particular application ofthe clamp changes, so has the particular construction of the clamp to beused. The result has been that if a person uses clamps for manydifferent purposes, he has usually been required to obtain a sepa rateclamp for each particular use. This problem is the reason for themultitude of various types and sizes of clamps available today on thecommercial market. What was heretofore missing, though it was clearlyneeded, is a clamping structure which is versatile enough to be used inmany different applications where previously many different specialclamps were needed.

SUMMARY OF THE INVENTION A versatile clamping apparatus having two clamparms which are pivotally attached intermediate the ends thereof, andadaptable to vary the pivotal point and the length of the clamp arms tothereby control the leverage factor and the speed of application offorces by the clamp. A unique jack screw connection aids in permittingthis movement of the pivotal point.

An object of the present invention is to provide a versatile clamp whichis adaptable to many different uses and applications.

Another object of the invention is to provide a clamping apparatus inwhich the pivotal point can be changed.

A further object of the invention is to provide a clamping apparatus inwhich the length of the lever arms may be changed.

A further object of the invention is to provide a clamp which may have aslow action and a high leverage factor, a fast action and a slowleverage factor or a reasonable range of speeds and leverage factorsinbetween.

Other objects, advantages, and novel features of the present inventionwill become apparent from the fol lowing detailed description of theinvention when con sidered in conjunction with the accompanying drawmgs.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a perspective view of theclamping apparatus of the instant invention;

FIG. 2 is a side elevational view of the present invention with aforward pivotal point being used;

FIG. 3 is a back end view of the clamp taken along line 3-3 of FIG. 2;

FIG. 4 is a crosssectional view of the clamp taken along line 4-4 ofFIG. 2; and

FIG. 5 is a side elevational viewsimilar to FIG. 2 but showing the clampusing a rear pivotal point.

DESCRIPTION OF THE PREFERRED I EMBODIMENT Referring now to the drawingswherein like reference numerals designate identical or correspondingparts throughout the several views, FIG. 1 shows the clamping device 10of the instant invention. A first elongated arm member 11 is pivotallyattached to a second arm member 12. Object engaging ends 13 and 14 onthe forward end of the clamp are controlled by a jack screw device 16 onthe rear end thereof.

The first elongated arm member 11 has an opening 17 in the front endthereof in which slidably disposed a bar 18 on the object engaging end13. The bar 18 can be adjusted to the desired length and tightened by aset screw device 19. Pivotally mounted to the object en:

gaging end 13 of the bar 18 is an object engaging member 21. Similarly,the second arm member 12 has an opening 22 in one end thereof in whichis slidably received a bar 23. This bar 23 is likewise adjustable andmay be fastened at its desired length by set screw device 24. The objectengaging end 14 of bar 23 has a turn thereon, with an object engagingsurface 26 on the remote end thereof. This object engaging surface 26 isdesigned to cooperate with object engaging member 21 on the firstelongated arm member 11.

The second arm member 12. is generally comprised of bar portion 23 withthe object engaging end 14 thereon, a generally horizontallongitudinally extending arm portion 27, second generally upstanding armportion 28 and a third generally horizontal arm portion 29. Front slots31 are formed in the front edge of second generally upstanding armportion 28 and rear slots 32 are formed in the back edge of generallyupstanding arm portion 28.

The second generally upstanding arm portion 28 of second arm member 12is received through an opening 33 in first elongated arm member 11. Afront pivotal rod 34 is disposed on the front side of the secondgenerally upstanding arm portion 28 and a rear pivotal rod 36 isdisposed through the opening 33 and on the back edge of second generallyupstanding arm portion 28. It can be seen from FIGS. 2 and 5, inparticular, that the front pivotal rod 34 can be received in any of thefront slots 31, or the back pivotal rod 36 may be received in any of therear slots 32 in the second generally upstanding arm portion 28.

-On the opposite end of first elongated member 11 from the objectengaging end 13 is a control end 37 having a pivotal bracket 38 thereon.This bracket 38 is pivoted by bolts 39, and has a threaded centralopening on the top side thereof. The third generally horizontally armportion 29 of second arm member 12 has an arcuate portion thereon with ahole centrally disposed therein. Extending through the hole is a controlrod 41 which is threadedly received in the opening in bracket 38 of thefirst elongated arm member 11. The hole in the third generallyhorizontal arm portion 29 is substantially larger than the size of thecontrol rod 41 received therein. Additionally sleeves 42 and 43, alongwith nuts 44 hold the controlled rod 41 in a fixed positionlongitudinally of the third generally horizontal arm portion 29, butsuch that it may rotate and rock slightly within the hole in the thirdgenerally horizontal arm portion 29. A handle 46 is attached to theupper end of control rod 41 for controlling the movement of the controlrod 41.

In operation it can be seen, for example in FIG. 2, that the frontpivotal rod 34 can be placed in the proper front slot 31 according tothe thickness of the object or objects to be clamped or the speed orleverage action desired. Additionally, the bars 18 and 23 may beadjusted to the desired lengths whereby they are directly above andbelow each other respectively. It can be seen that the object engagingmember 21 will be parallel with the object engaging surface 26 becauseof the pivoted construction of the object engaging member 21. It willalso be understood by those skilled in the art that if the object orobjects to be clamped are not parallel, then the pivot on objectengaging member 21 will allow this member 21 to conform to whateverangle is needed. Once the object or objects 47 are placed on the objectengaging surface 26, the jack screw device 16 is then screwed togetheruntil the object engaging member 21 firmly presses against the objectand against the object engaging surface 26. At that point the clampingis complete and the clamp will hold until the jack screw device 16 isreversed to release the objects 47.

Referring now to FIG. it can be seen that the rear pivotal rod 36 isreceived in one of the rear slots 32, which are slightly upwardlyextending. The objects 48 are placed on the object engaging surface 26and the jack screw device is then screwed together so as to clamp theobject engaging member 21 as explained above with respect to the forwardpivotal position. It can be seen in FIG. 5 that the control rod 41 ismisaligned with the hole in the third generally horizontal arm portion29 so that the jack screw forces can most efficiently be used. Alsoaiding in the efficiency of forces is the arcuate portion of the thirdgenerally horizontal arm portion 29 which allows more of the surface ofsleeve 42 to contact the third generally horizontal arm portion 29 andtherefore distribute the forces applied thereto. It can also be seen inFIGS. 2 and 5 that the bracket 38 prevents any torque forces from beingapplied to the control rod 41 which would be caused if this pivotalconnection was not provided, and which would interfere with the properthreadedly engaging relationship between the control rod 41 and thebracket 38.

It can therefore be seen that the above stated objects have beenaccomplished in providing an extremely versatile clamp which isadaptable to a multitude of uses and thereby replaces the need to usemany different specialized clamps.

Obviously many modifications and variations of the present invention arepossible in light of the above teachings. It is therefore to beunderstood that, within the scope of the appended claims, the inventionmay be practiced otherwise than as specifically described.

I claim:

1. A clamp comprising:

a first elongated arm member having an object engaging end and a controlend;

a second arm member having an object engaging end and a control end;

means for pivotally connecting said first and second arms intermediatethe ends thereof; and

means for varying the distance between the pivotal connection and theobject engaging ends of said first and second arm members, said distancevarying means comprising two spaced pivotal rods on said first armmember and at least one opening in said second arm member for receivingeach of said pivotal rods, and wherein a plurality of slot shapedopenings are disposed on opposite edges of said second arm member, theslot shaped opening on one edge being adapted to pivotally receive oneof said pivotal rods and the slot shaped openings on the other edge ofsaid second arm member being adapted to pivotally receive the other ofsaid pivotal rods.

2. A clamp comprising:

a first elongated arm member having an object engaging end and a controlend; i

a second arm member having an object engaging end and a control end,said second arm member comprising a first generally horizontallongitudinally extending arm portion, a second generally upstanding armportion connected at one end thereto at a point remote from the objectengaging end of the second arm member, said second generally upstandingarm portion having a front and a back edge, and a third generallyhorizontal arm portion connected to the other end of the second armportion and extending in a direction away from the object engaging endof the second arm member;

at least one slot being disposed in the front edge of said secondgenerally upstanding portion of said second arm member and at least oneslot being disposed in the back edge of said second generally upstandingportion of said second arm member;

a first pivotal rod connected to said first arm member being disposed onone side of said second generally upstanding portion of said second armmember and adapted to be received in the slot in the front edge of saidsecond generally upstanding portion;

a second pivotal rod spaced from said first pivotal rod being connectedto said first arm member and disposed on another side of said secondgenerally upstanding portion of said second arm member and adapted to bereceived in the slot in the back edge of said second generallyupstanding portion; and

means for varying the distance between the pivotal connection and theobject engaging ends of said first and second arm members.

3. The clamp of claim 2 having means for controlling the relativemovement of the control ends of said first and second arm members, andthereby controlling the object engaging ends of said first and secondarm members.

4. The clamp of claim 3 wherein the control means comprises a jack screwdevice including a hole in the control end of the second arm member, acontrol rod pivotally mounted within the hole, a bracket pivotallyattached to the control end the first arm member, said control rodthreadedly engaging said bracket, and means for facilitating rotation ofthe control rod to thereby move the control ends of the first and secondarm members with respect to each other.

5. The clamp of claim 2 wherein a plurality of slots are disposed on thefront and back edges of said second generally upstanding portion of saidsecond arm memface on the object engaging end thereof which lies in agenerally horizontal plane parallel to the general longitudinal axis ofthe generally horizontal arm portion of the second arm member.

1. A clamp comprising: a first elongated arm member having an objectengaging end and a control end; a second arm member having an objectengaging end and a control end; means for pivotally connecting saidfirst and second arms intermediate the ends thereof; and means forvarying the distance between the pivotal connection and the objectengaging ends of said first and second arm members, said distancevarying means comprising two spaced pivotal rods on said first armmember and at least one opening in said second arm member for receivingeach of said pivotal rods, and wherein a plurality of slot shapedopenings are disposed on opposite edges of said second arm member, theslot shaped opening on one edge being adapted to pivotally receive oneof said pivotal rods and the slot shaped openings on the other edge ofsaid second arm member being adapted to pivotally receive the other ofsaid pivotal rods.
 2. A clamp comprising: a first elongated arm memberhaving an object engaging end and a control end; a second arm memberhaving an object engaging end and a control end, said second arm membercomprising a first generally horizontal longitudinally extending armportion, a second generally upstanding arm portion connected at one endthereto at a point remote from the object engaging end of the second armmember, said second generally upstanding arm portion having a front anda back edge, and a third generally horizontal arm portion connected tothe other end of the second arm portion and extending in a directionaway from the object engaging end of the second arm member; at least oneslot being disposed in the front edge of said second generallyupstanding portion of said second arm member and at least one slot beingdisposed in the back edge of said second generally Upstanding portion ofsaid second arm member; a first pivotal rod connected to said first armmember being disposed on one side of said second generally upstandingportion of said second arm member and adapted to be received in the slotin the front edge of said second generally upstanding portion; a secondpivotal rod spaced from said first pivotal rod being connected to saidfirst arm member and disposed on another side of said second generallyupstanding portion of said second arm member and adapted to be receivedin the slot in the back edge of said second generally upstandingportion; and means for varying the distance between the pivotalconnection and the object engaging ends of said first and second armmembers.
 3. The clamp of claim 2 having means for controlling therelative movement of the control ends of said first and second armmembers, and thereby controlling the object engaging ends of said firstand second arm members.
 4. The clamp of claim 3 wherein the controlmeans comprises a jack screw device including a hole in the control endof the second arm member, a control rod pivotally mounted within thehole, a bracket pivotally attached to the control end the first armmember, said control rod threadedly engaging said bracket, and means forfacilitating rotation of the control rod to thereby move the controlends of the first and second arm members with respect to each other. 5.The clamp of claim 2 wherein a plurality of slots are disposed on thefront and back edges of said second generally upstanding portion of saidsecond arm member.
 6. The clamp of claim 4 wherein said hole issubstantially larger than said control rod to permit substantialmisalignment of the rod with respect to the hole.
 7. The clamp of claim6 wherein the portion of said third generally horizontal arm portionhaving the hole therein is of an arcuate configuration to therebyfacilitate easier misalignment of the control rod with respect to thehole.
 8. The clamp of claim 7 wherein the first elongated arm member hasmeans for adjusting the length thereof on the object engaging end; andmeans for adjusting the length of the second arm member on the objectengaging end thereof.
 9. The clamp of claim 8 said first elongated armmember has an object engaging member pivotally attached to the objectengaging end thereof; and said second arm member has an object engagingsurface on the object engaging end thereof which lies in a generallyhorizontal plane parallel to the general longitudinal axis of thegenerally horizontal arm portion of the second arm member.